Most of our code was including Log.h even though that is not where the
"lldb" log channel is defined (Log.h defines the generic logging
infrastructure). This worked because Log.h included Logging.h, even
though it should.
After the recent refactor, it became impossible the two files include
each other in this direction (the opposite inclusion is needed), so this
patch removes the workaround that was put in place and cleans up all
files to include the right thing. It also renames the file to LLDBLog to
better reflect its purpose.
Add Thread::GetSiginfo() and SBThread::GetSiginfo() methods to retrieve
the siginfo value from server.
Differential Revision: https://reviews.llvm.org/D118055
Add Thread::GetSiginfo() and SBThread::GetSiginfo() methods to retrieve
the siginfo value from server.
Differential Revision: https://reviews.llvm.org/D118055
This patch introduces a new SBAPI method: `SBModule::IsFileBacked`
As the name suggests, it tells the user if the module's object file is
on disk or in memory.
rdar://68538278
Differential Revision: https://reviews.llvm.org/D118261
Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
Remove the last remaining references to the reproducers from the
instrumentation. This patch renames the relevant files and macros.
Differential revision: https://reviews.llvm.org/D117712
It complements the existing SBDebugger::SetCurrentPlatformSDKRoot and
allows one to set the sysroot of a platform without making it current.
Differential Revision: https://reviews.llvm.org/D117550
This macro was being used to select the proper import/export annotations
on SB classes. Non-windows clients do not have such requirements.
Instead introduce a new macro (LLDB_IN_LIBLLDB), which signals that
we're compiling liblldb itself (and should use dllexport). The default
(no macro) is to use dllimport. I've moved the macro definition to
SBDefines.h, since it only makes sense when building the API library.
Differential Revision: https://reviews.llvm.org/D117564
Until the introduction of the C++ REPL, there was always a single REPL
language. Several places relied on this assumption through
repl_languages.GetSingularLanguage. Now that this is no longer the case,
we need a way to specify a selected/preferred REPL language. This patch
does that with the help of a debugger property, taking inspiration from
how we store the scripting language.
Differential revision: https://reviews.llvm.org/D116697
This is a re-submission of 24d2405588
without the hunks in HostNativeThreadBase.{h,cpp}, which break builds
on Windows.
Identified with modernize-use-nullptr.
This reverts commit 913457acf0.
It again broke builds on Windows:
lldb/source/Host/common/HostNativeThreadBase.cpp(37,14): error:
assigning to 'lldb::thread_result_t' (aka 'unsigned int') from
incompatible type 'std::nullptr_t'
This is a re-submission of 24d2405588
without the hunk in HostNativeThreadBase.h, which breaks builds on
Windows.
Identified with modernize-use-nullptr.
This reverts commit 24d2405588.
Breaks building on Windows:
../../lldb/include\lldb/Host/HostNativeThreadBase.h(49,36): error:
cannot initialize a member subobject of type 'lldb::thread_result_t'
(aka 'unsigned int') with an rvalue of type 'std::nullptr_t'
lldb::thread_result_t m_result = nullptr;
^~~~~~~
1 error generated.
Introduce a FreeBSDKernel plugin that provides the ability to read
FreeBSD kernel core dumps. The plugin utilizes libfbsdvmcore to provide
support for both "full memory dump" and minidump formats across variety
of architectures supported by FreeBSD. It provides the ability to read
kernel memory, as well as the crashed thread status with registers
on arm64, i386 and x86_64.
Differential Revision: https://reviews.llvm.org/D114911
StructuredDataImpl ownership semantics is unclear at best. Various
structures were holding a non-owning pointer to it, with a comment that
the object is owned somewhere else. From what I was able to gather that
"somewhere else" was the SBStructuredData object, but I am not sure that
all created object eventually made its way there. (It wouldn't matter
even if they did, as we are leaking most of our SBStructuredData
objects.)
Since StructuredDataImpl is just a collection of two (shared) pointers,
there's really no point in elaborate lifetime management, so this patch
replaces all StructuredDataImpl pointers with actual objects or
unique_ptrs to it. This makes it much easier to resolve SBStructuredData
leaks in a follow-up patch.
Differential Revision: https://reviews.llvm.org/D114791
This patch introduces a new method to SBData: SetDataWithOwnership.
Instead of referencing the pointer to the data, this method copies the
data buffer into lldb's heap memory.
This can prevent having the underlying DataExtractor object point to
freed/garbage-collected memory.
Differential Revision: https://reviews.llvm.org/D115652
Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
Because of its dependency on clang (and potentially other compilers
downstream, such as swift) lldb_private::GetVersion already lives in its
own library called lldbBase. Despite that, its implementation was spread
across unrelated files. This patch improves things by introducing a
Version library with its own directory, header and implementation file.
The benefits of this patch include:
- We can get rid of the ugly quoting macros.
- Other parts of LLDB can read the version number from
lldb/Version/Version.inc.
- The implementation can be swapped out for tools like lldb-server than
don't need to depend on clang at all.
Differential revision: https://reviews.llvm.org/D115211
Right now if the LLDB is compiled under the windows with static vcruntime library, the -o and -k commands will not work.
The problem is that the LLDB create FILE* in lldb.exe and pass it to liblldb.dll which is an object from CRT.
Since the CRT is statically linked each of these module has its own copy of the CRT with it's own global state and the LLDB should not share CRT objects between them.
In this change I moved the logic of creating FILE* out of commands stream from Driver class to SBDebugger.
To do this I added new method: SBError SBDebugger::SetInputStream(SBStream &stream)
Command to build the LLDB:
cmake -G Ninja -DLLVM_ENABLE_PROJECTS="clang;lldb;libcxx" -DLLVM_USE_CRT_RELEASE="MT" -DLLVM_USE_CRT_MINSIZEREL="MT" -DLLVM_USE_CRT_RELWITHDEBINFO="MT" -DP
YTHON_HOME:FILEPATH=C:/Python38 -DCMAKE_C_COMPILER:STRING=cl.exe -DCMAKE_CXX_COMPILER:STRING=cl.exe ../llvm
Command which will fail:
lldb.exe -o help
See discord discussion for more details: https://discord.com/channels/636084430946959380/636732809708306432/854629125398724628
This revision is for the further discussion.
Reviewed By: teemperor
Differential Revision: https://reviews.llvm.org/D104413
This diff is adding the capping_size determination for the list and forward list, to limit the number of children to be displayed. Also it modifies and unifies tests for libcxx and libstdcpp list data formatter.
Reviewed By: wallace
Differential Revision: https://reviews.llvm.org/D114433
[NFC] As part of using inclusive language within the llvm project, this patch
renames master plan to controlling plan in lldb.
Reviewed By: jingham
Differential Revision: https://reviews.llvm.org/D113019
It is surprisingly difficult to write a simple python script that
can reliably `import lldb` without failing, or crashing. I'm
currently resorting to convolutions like this:
def find_lldb(may_reexec=False):
if prefix := os.environ.get('LLDB_PYTHON_PREFIX'):
if os.path.realpath(prefix) != os.path.realpath(sys.prefix):
raise Exception("cannot import lldb.\n"
f" sys.prefix should be: {prefix}\n"
f" but it is: {sys.prefix}")
else:
line1, line2 = subprocess.run(
['lldb', '-x', '-b', '-o', 'script print(sys.prefix)'],
encoding='utf8', stdout=subprocess.PIPE,
check=True).stdout.strip().splitlines()
assert line1.strip() == '(lldb) script print(sys.prefix)'
prefix = line2.strip()
os.environ['LLDB_PYTHON_PREFIX'] = prefix
if sys.prefix != prefix:
if not may_reexec:
raise Exception(
"cannot import lldb.\n" +
f" This python, at {sys.prefix}\n"
f" does not math LLDB's python at {prefix}")
os.environ['LLDB_PYTHON_PREFIX'] = prefix
python_exe = os.path.join(prefix, 'bin', 'python3')
os.execl(python_exe, python_exe, *sys.argv)
lldb_path = subprocess.run(['lldb', '-P'],
check=True, stdout=subprocess.PIPE,
encoding='utf8').stdout.strip()
sys.path = [lldb_path] + sys.path
This patch aims to replace all that with:
#!/usr/bin/env lldb-python
import lldb
...
... by adding the following features:
* new command line option: --print-script-interpreter-info. This
prints language-specific information about the script interpreter
in JSON format.
* new tool (unix only): lldb-python which finds python and exec's it.
Reviewed By: JDevlieghere
Differential Revision: https://reviews.llvm.org/D112973
This patch adds a new `StructuredData::Dictionary` constructor that
takes a `StructuredData::ObjectSP` as an argument. This is used to pass
the opaque_ptr from the `SBStructuredData` used to initialize a
ScriptedProecss, to the `ProcessLaunchInfo` class.
This also updates `SBLaunchInfo::SetScriptedProcessDictionary` to
reflect the formentionned changes which solves the nullptr deref.
Differential Revision: https://reviews.llvm.org/D112107
Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
The amount of roundtrips between StringRefs, ConstStrings and std::strings is
getting a bit out of hand, this patch avoid the unnecessary roundtrips.
Reviewed By: wallace, aprantl
Differential Revision: https://reviews.llvm.org/D112863
The new module stats adds the ability to measure the time it takes to parse and index the symbol tables for each module, and reports modules statistics in the output of "statistics dump" along with the path, UUID and triple of the module. The time it takes to parse and index the symbol tables are also aggregated into new top level key/value pairs at the target level.
Differential Revision: https://reviews.llvm.org/D112279
This patch is a smaller version of a previous patch https://reviews.llvm.org/D110804.
This patch modifies the output of "statistics dump" to be able to get stats from the current target. It adds 3 new stats as well. The output of "statistics dump" is now emitted as JSON so that it can be used to track performance and statistics and the output could be used to populate a database that tracks performance. Sample output looks like:
(lldb) statistics dump
{
"expressionEvaluation": {
"failures": 0,
"successes": 0
},
"firstStopTime": 0.34164492800000001,
"frameVariable": {
"failures": 0,
"successes": 0
},
"launchOrAttachTime": 0.31969605400000001,
"targetCreateTime": 0.0040863039999999998
}
The top level keys are:
"expressionEvaluation" which replaces the previous stats that were emitted as plain text. This dictionary contains the success and fail counts.
"frameVariable" which replaces the previous stats for "frame variable" that were emitted as plain text. This dictionary contains the success and fail counts.
"targetCreateTime" contains the number of seconds it took to create the target and load dependent libraries (if they were enabled) and also will contain symbol preloading times if that setting is enabled.
"launchOrAttachTime" is the time it takes from when the launch/attach is initiated to when the first private stop occurs.
"firstStopTime" is the time in seconds that it takes to stop at the first stop that is presented to the user via the LLDB interface. This value will only have meaning if you set a known breakpoint or stop location in your code that you want to measure as a performance test.
This diff is also meant as a place to discuess what we want out of the "statistics dump" command before adding more funcionality. It is also meant to clean up the previous code that was storting statistics in a vector of numbers within the lldb_private::Target class.
Differential Revision: https://reviews.llvm.org/D111686
This patch deals with ObjectFile, ObjectContainer and OperatingSystem
plugins. I'll convert the other types in separate patches.
In order to enable piecemeal conversion, I am leaving some ConstStrings
in the lowest PluginManager layers. I'll convert those as the last step.
Differential Revision: https://reviews.llvm.org/D112061
The point is to allow users with a related set of script based commands
to organize their commands in a hierarchy in the command set, rather than
having to have only top-level commands.
Differential Revision: https://reviews.llvm.org/D110298
There is no reason why this function should be returning a ConstString.
While modifying these files, I also fixed several instances where
GetPluginName and GetPluginNameStatic were returning different strings.
I am not changing the return type of GetPluginNameStatic in this patch, as that
would necessitate additional changes, and this patch is big enough as it is.
Differential Revision: https://reviews.llvm.org/D111877
Add necessary typemaps for Lua bindings, together with some other files.
Signed-off-by: Siger Yang <sigeryeung@gmail.com>
Reviewed By: tammela
Differential Revision: https://reviews.llvm.org/D108090
This patch adds support for memory regions in Scripted Processes.
This is necessary to read the stack memory region in order to
reconstruct each stackframe of the program.
In order to do so, this patch makes some changes to the SBAPI, namely:
- Add a new constructor for `SBMemoryRegionInfo` that takes arguments
such as the memory region name, address range, permissions ...
This is used when reading memory at some address to compute the offset
in the binary blob provided by the user.
- Add a `GetMemoryRegionContainingAddress` method to `SBMemoryRegionInfoList`
to simplify the access to a specific memory region.
With these changes, lldb is now able to unwind the stack and reconstruct
each frame. On top of that, reloading the target module at offset 0 allows
lldb to symbolicate the `ScriptedProcess` using debug info, similarly to an
ordinary Process.
To test this, I wrote a simple program with multiple function calls, ran it in
lldb, stopped at a leaf function and read the registers values and copied
the stack memory into a binary file. These are then used in the python script.
Differential Revision: https://reviews.llvm.org/D108953
Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
.. and reduce the scope of others. They don't follow llvm coding
standards (which say they should be used only when the same effect
cannot be achieved with the static keyword), and they set a bad example.
Update GetRegisterInfoByName() methods to support getting registers
by a generic name independently of alt_name entries in the register
context. This makes it possible to use generic names when interacting
with gdbserver (that does not supply alt_names). It also makes it
possible to remove some of the duplicated information from register
context declarations and/or use alt_names for another purpose.
Differential Revision: https://reviews.llvm.org/D108554
This change adds save-core functionality into the ObjectFileELF that enables
saving minidump of a stopped process. This change is mainly targeting Linux
running on x86_64 machines. Minidump should contain basic information needed
to examine state of threads, local variables and stack traces. Full support
for other platforms is not so far implemented. API tests are using LLDB's
MinidumpParser.
This relands commit aafa05e, reverted in 1f986f6.
Failed tests were fixed.
Reviewed By: clayborg
Differential Revision: https://reviews.llvm.org/D108233
This change adds save-core functionality into the ObjectFileELF that enables
saving minidump of a stopped process. This change is mainly targeting Linux
running on x86_64 machines. Minidump should contain basic information needed
to examine state of threads, local variables and stack traces. Full support
for other platforms is not so far implemented. API tests are using LLDB's
MinidumpParser.
Reviewed By: clayborg
Differential Revision: https://reviews.llvm.org/D108233
In 9ea6dd5cfa /
https://reviews.llvm.org/D88387 where I added skinny corefile
creation, I added new SB API and tried to manually update the hooks
for the reproducers. I missed a spot, and I should have used
lldb-instr to update the instrumentation automatically.
Modify OpenOptions enum to open the future path into synchronizing
vFile:open bits with GDB. Currently, LLDB and GDB use different flag
models effectively making it impossible to match bits. Notably, LLDB
uses two bits to indicate read and write status, and uses union of both
for read/write. GDB uses a value of 0 for read-only, 1 for write-only
and 2 for read/write.
In order to future-proof the code for the GDB variant:
1. Add a distinct eOpenOptionReadWrite constant to be used instead
of (eOpenOptionRead | eOpenOptionWrite) when R/W access is required.
2. Rename eOpenOptionRead and eOpenOptionWrite to eOpenOptionReadOnly
and eOpenOptionWriteOnly respectively, to make it clear that they
do not mean to be combined and require update to all call sites.
3. Use the intersection of all three flags when matching against
the three possible values.
This commit does not change the actual bits used by LLDB.
Differential Revision: https://reviews.llvm.org/D106984
They used to be referenced from the .xcodeproj files, but those are long gone.
No behavior change.
Differential Revision: https://reviews.llvm.org/D107444
Rather than passing two booleans around, which is especially error prone
with them being next to each other, use a struct with named fields
instead.
Differential revision: https://reviews.llvm.org/D107295
This change adds AllocateMemory and DeallocateMemory methods to the SBProcess
API, so that clients can allocate and deallocate memory blocks within the
process being debugged (for storing JIT-compiled code or other uses).
(I am developing a debugger + REPL using the API; it will need to store
JIT-compiled code within the target.)
Reviewed By: clayborg, jingham
Differential Revision: https://reviews.llvm.org/D105389
Replacing existing uses with AppendError.
SetError is also part of the SBI API. This remains
but instead of calling the underlying SetError it
will call AppendError.
Reviewed By: teemperor
Differential Revision: https://reviews.llvm.org/D104768
Add a new feature to process save-core on Darwin systems -- for
lldb to create a user process corefile with only the dirty (modified
memory) pages included. All of the binaries that were used in the
corefile are assumed to still exist on the system for the duration
of the use of the corefile. A new --style option to process save-core
is added, so a full corefile can be requested if portability across
systems, or across time, is needed for this corefile.
debugserver can now identify the dirty pages in a memory region
when queried with qMemoryRegionInfo, and the size of vm pages is
given in qHostInfo.
Create a new "all image infos" LC_NOTE for Mach-O which allows us
to describe all of the binaries that were loaded in the process --
load address, UUID, file path, segment load addresses, and optionally
whether code from the binary was executing on any thread. The old
"read dyld_all_image_infos and then the in-memory Mach-O load
commands to get segment load addresses" no longer works when we
only have dirty memory.
rdar://69670807
Differential Revision: https://reviews.llvm.org/D88387
This adds a basic SB API for creating and stopping traces.
Note: This doesn't add any APIs for inspecting individual instructions. That'd be a more complicated change and it might be better to enhande the dump functionality to output the data in binary format. I'll leave that for a later diff.
This also enhances the existing tests so that they test the same flow using both the command interface and the SB API.
I also did some cleanup of legacy code.
Differential Revision: https://reviews.llvm.org/D103500
Since https://reviews.llvm.org/D103701 AppendError<...>
sets this for you.
This change includes all of the non-command uses.
Some uses remain where it's either tricky to reason about
the logic, or they aren't paired with AppendError calls.
Reviewed By: teemperor
Differential Revision: https://reviews.llvm.org/D104379
This is an NFC cleanup.
Many of the API's that returned BreakpointOptions always returned valid ones.
Internally the BreakpointLocations usually have null BreakpointOptions, since they
use their owner's options until an option is set specifically on the location.
So the original code used pointers & unique_ptr everywhere for consistency.
But that made the code hard to reason about from the outside.
This patch changes the code so that everywhere an API is guaranteed to
return a non-null BreakpointOption, it returns it as a reference to make
that clear.
It also changes the Breakpoint to hold a BreakpointOption
member where it previously had a UP. Since we were always filling the UP
in the Breakpoint constructor, having the UP wasn't helping anything.
Differential Revision: https://reviews.llvm.org/D104162
This workaround was necessary before the major changes of managing python versions, but it is not needed anymore.
Reviewed By: JDevlieghere
Differential Revision: https://reviews.llvm.org/D104047
This converts a default constructor's member initializers into C++11
default member initializers. This patch was automatically generated with
clang-tidy and the modernize-use-default-member-init check.
$ run-clang-tidy.py -header-filter='lldb' -checks='-*,modernize-use-default-member-init' -fix
This is a mass-refactoring patch and this commit will be added to
.git-blame-ignore-revs.
Differential revision: https://reviews.llvm.org/D103483
This is another step towards implementing the equivalent of
`platform process list` and related functionality.
`uint32_t` is used for the argument count and index despite the
underlying value being `size_t` to be consistent with other
index-based access to arguments.
Differential Revision: https://reviews.llvm.org/D103675
This is present when doing a `platform process list` and is
tracked by the underlying code. To do something like the
process list via the SB API in the future, this must be
exposed.
Differential Revision: https://reviews.llvm.org/D103375
The C headers are deprecated so as requested in D102845, this is replacing them
all with their (not deprecated) C++ equivalent.
Reviewed By: shafik
Differential Revision: https://reviews.llvm.org/D103084
A long time ago LLDB wanted to start using StringRef instead of
C-Strings/ConstString but was blocked by the fact that the StringRef constructor
that takes a C-string was asserting that the C-string isn't a nullptr. To
workaround this, D24697 introduced a special function called `withNullAsEmpty`
and that's what LLDB (and only LLDB) started to use to build StringRefs from
C-strings.
A bit later it seems that `withNullAsEmpty` was declared too awkward to use and
instead the assert in the StringRef constructor got removed (see D24904). The
rest of LLDB was then converted to StringRef by just calling the now perfectly
usable implicit constructor.
However, all the calls to `withNullAsEmpty` just remained and are now just
strange artefacts in the code base that just look out of place. It's also
curiously a LLDB-exclusive function and no other project ever called it since
it's introduction half a decade ago.
This patch removes all uses of `withNullAsEmpty`. The follow up will be to
remove the function from StringRef.
Reviewed By: JDevlieghere
Differential Revision: https://reviews.llvm.org/D102597
This patch updates `SBCompileUnit::FindLineEntryIndex` to pass a valid
`LineEntry` pointer to `CompileUnit::FindLineEntry`.
This caused `LineTable::FindLineEntryIndexByFileIndexImpl` to return its
`best_match` initial value (UINT32_MAX).
rdar://78115426
Differential Revision: https://reviews.llvm.org/D102658
Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
Fix cases that can crash `SBStructuredData::operator=`.
This happened in a case where `rhs` had a null `SBStructuredDataImpl`.
Differential Revision: https://reviews.llvm.org/D101585
This patch refactors a good part of the code base turning the usual
FileSpec, Line, Column, CheckInlines, ExactMatch arguments into a
SourceLocationSpec object.
This change is required for a following patch that will add handling of the
column line information when doing symbol resolution.
Differential Revision: https://reviews.llvm.org/D100965
Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
This patch moves the Declaration class from the Symbol library to the
Core library. This will allow to use it in a more generic fashion and
aims to lower the dependency cycles when it comes to the linking.
The patch also does some cleaning up by making column information
permanent and removing the LLDB_ENABLE_DECLARATION_COLUMNS directives.
Differential revision: https://reviews.llvm.org/D101556
Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
Introduce three new stop reasons for fork, vfork and vforkdone events.
This includes server support for serializing fork/vfork events into
gdb-remote protocol. The stop infos for the two base events take a pair
of PID and TID for the newly forked process.
Differential Revision: https://reviews.llvm.org/D100196
Commiting this patch for Augusto Noronha who is getting set
up still.
This patch changes Target::ReadMemory so the default behavior
when a read is in a Section that is read-only is to fetch the
data from the local binary image, instead of reading it from
memory. Update all callers to use their old preferences
(the old prefer_file_cache bool) using the new API; we should
revisit these calls and see if they really intend to read
live memory, or if reading from a read-only Section would be
equivalent and important for performance-sensitive cases.
rdar://30634422
Differential revision: https://reviews.llvm.org/D100338
Since quite a while Apple's LLDB fork (that contains the Swift debugging
support) is randomly crashing in `CommandLineParser::addOption` with an error
such as `CommandLine Error: Option 'h' registered more than once!`
The backtrace of the crashing thread is shown below. There are also usually many
other threads also performing similar clang::FrontendActions which are all
trying to generate (usually outdated) Clang modules which are used by Swift for
various reasons.
```
[ 6] LLDB`CommandLineParser::addOption(llvm:🆑:Option*, llvm:🆑:SubCommand*) + 856
[ 7] LLDB`CommandLineParser::addOption(llvm:🆑:Option*, llvm:🆑:SubCommand*) + 733
[ 8] LLDB`CommandLineParser::addOption(llvm:🆑:Option*, bool) + 184
[ 9] LLDB`llvm:🆑:ParseCommandLineOptions(...) [inlined] ::CommandLineParser::ParseCommandLineOptions(... + 1279
[ 9] LLDB`llvm:🆑:ParseCommandLineOptions(...) + 497
[ 10] LLDB`setCommandLineOpts(clang::CodeGenOptions const&) + 416
[ 11] LLDB`EmitAssemblyHelper::EmitAssemblyWithNewPassManager(...) + 98
[ 12] LLDB`clang::EmitBackendOutput(...) + 4580
[ 13] LLDB`PCHContainerGenerator::HandleTranslationUnit(clang::ASTContext&) + 871
[ 14] LLDB`clang::MultiplexConsumer::HandleTranslationUnit(clang::ASTContext&) + 43
[ 15] LLDB`clang::ParseAST(clang::Sema&, bool, bool) + 579
[ 16] LLDB`clang::FrontendAction::Execute() + 74
[ 17] LLDB`clang::CompilerInstance::ExecuteAction(clang::FrontendAction&) + 1808
```
The underlying reason for the crash is that the CommandLine code in LLVM isn't
thread-safe and will never be thread-safe with its current architecture. The way
LLVM's CommandLine logic works is that all parts of the LLVM can provide command
line arguments by defining `cl::opt` global variables and their constructors
(which are invoked during static initialisation) register the variable in LLVM's
CommandLineParser (which is also just a global variable). At some later point
after static initialization we actually try to parse command line arguments and
we ask the CommandLineParser to parse our `argv`. The CommandLineParser then
lazily constructs it's internal parsing state in a non-thread-safe way (this is
where the crash happens), parses the provided command line and then goes back to
the respective `cl::opt` global variables and sets their values according to the
parse result.
As all of this is based on global state, this whole mechanism isn't thread-safe
so the only time to ever use it is when we know we only have one active thread
dealing with LLVM logic. That's why nearly all callers of
`llvm:🆑:ParseCommandLineOptions` are at the top of the `main` function of the
some LLVM-based tool. One of the few exceptions to this rule is in the
`setCommandLineOpts` function in `BackendUtil.cpp` which is in our backtrace:
```
static void setCommandLineOpts(const CodeGenOptions &CodeGenOpts) {
SmallVector<const char *, 16> BackendArgs;
BackendArgs.push_back("clang"); // Fake program name.
if (!CodeGenOpts.DebugPass.empty()) {
BackendArgs.push_back("-debug-pass");
BackendArgs.push_back(CodeGenOpts.DebugPass.c_str());
}
if (!CodeGenOpts.LimitFloatPrecision.empty()) {
BackendArgs.push_back("-limit-float-precision");
BackendArgs.push_back(CodeGenOpts.LimitFloatPrecision.c_str());
}
BackendArgs.push_back(nullptr);
llvm:🆑:ParseCommandLineOptions(BackendArgs.size() - 1,
BackendArgs.data());
}
```
This is trying to set `cl::opt` variables in the LLVM backend to their right
value as the passed via CodeGenOptions by invoking the CommandLine parser. As
this is just in some generic Clang CodeGen code (where we allow having multiple
threads) this is code is clearly wrong. If we're unlucky it either overwrites
the value of the global variables or it causes the CommandLine parser to crash.
So the next question is why is this only crashing in LLDB? The main reason seems
to be that easiest way to crash this code is to concurrently enter the initial
CommandLineParser construction where it tries to collect all the registered
`cl::opt` options and checks for sanity:
```
// If it's a DefaultOption, check to make sure it isn't already there.
if (O->isDefaultOption() &&
SC->OptionsMap.find(O->ArgStr) != SC->OptionsMap.end())
return;
// Add argument to the argument map!
if (!SC->OptionsMap.insert(std::make_pair(O->ArgStr, O)).second) {
errs() << ProgramName << ": CommandLine Error: Option '" << O->ArgStr
<< "' registered more than once!\n";
HadErrors = true;
}
```
The `OptionsMap` here is global variable and if we end up in this code with two
threads at once then two threads at the same time can register an option (such
as 'h') when they pass the first `if` and then we fail with the sanity check in
the second `if`.
After this sanity check and initial setup code the only remaining work is just
parsing the provided CommandLine which isn't thread-safe but at least doesn't
crash in all my attempts at breaking it (as it's usually just reading from the
already generated parser state but not further modifying it). The exception to
this is probably that once people actually specify the options in the code
snippet above we might run into some new interesting ways to crash everything.
To go back to why it's only affecting LLDB: Nearly all LLVM tools I could find
(even if they are using threads) seem to call the CommandLine parser at the
start so they all execute the initial parser setup at a point where there is
only one thread. So once the code above is executed they are mostly safe from
the sanity check crashes. We even have some shady code for the gtest `main` in
`TestMain.cpp` which is why this also doesn't affect unit tests.
The only exception to this rule is ... *drum roll* ... LLDB! it's not using that
CommandLine library for parsing options so it also never ends up calling it in
`main`. So when we end up in the `FrontendAction` code from the backtrace we are
already very deep in some LLDB logic and usually already have several threads.
In a situation where Swift decides to compile a large amount of Clang modules in
parallel we then end up entering this code via several threads. If several
threads reach this code at the same time we end up in the situation where the
sanity-checking code of CommandLine crashes. I have a very reliable way of
demonstrating the whole thing in D99650 (just run the unit test several times,
it usually crashes after 3-4 attempts).
We have several ways to fix this:
1. Make the whole CommandLine mechanism in LLVM thread-safe.
2. Get rid of `setCommandLineOpts` in `BackendUtil.cpp` and other callers of the
command line parsing in generic Clang code.
3. Initialise the CommandLine library in a safe point in LLDB.
Option 1 is just a lot of work and I'm not even sure where to start. The whole
mechanism is based on global variables and global state and this seems like a
humongous task.
Option 2 is probably the best thing we can do in the near future. There are only
two callers of the command line parser in generic Clang code. The one in
`BackendUtils.cpp` looks like it can be replaced with some reasonable
refactoring (as it only deals with two specific options). There is another one
in `ExecuteCompilerInvocation` which deals with forwarding the generic `-mllvm`
options to the backend which seems like it will just end up requiring us to do
Option 1.
Option 3 is what this patch is doing. We just parse some dummy command line
invocation in a point of the LLDB execution where we only have one thread that
is dealing with LLVM/Clang stuff. This way we are at least prevent the frequent
crashes for users as parsing the dummy command line invocation will set up the
initial parser state safely.
Fixes rdar://70989856
Reviewed By: mib, JDevlieghere
Differential Revision: https://reviews.llvm.org/D99652
This implements the interactive trace start and stop methods.
This diff ended up being much larger than I anticipated because, by doing it, I found that I had implemented in the beginning many things in a non optimal way. In any case, the code is much better now.
There's a lot of boilerplate code due to the gdb-remote protocol, but the main changes are:
- New tracing packets: jLLDBTraceStop, jLLDBTraceStart, jLLDBTraceGetBinaryData. The gdb-remote packet definitions are quite comprehensive.
- Implementation of the "process trace start|stop" and "thread trace start|stop" commands.
- Implementaiton of an API in Trace.h to interact with live traces.
- Created an IntelPTDecoder for live threads, that use the debugger's stop id as checkpoint for its internal cache.
- Added a functionality to stop the process in case "process tracing" is enabled and a new thread can't traced.
- Added tests
I have some ideas to unify the code paths for post mortem and live threads, but I'll do that in another diff.
Differential Revision: https://reviews.llvm.org/D91679
LLDB can often appear deadlocked to users that use IDEs when it is indexing DWARF, or parsing symbol tables. These long running operations can make a debug session appear to be doing nothing even though a lot of work is going on inside LLDB. This patch adds a public API to allow clients to listen to debugger events that report progress and will allow UI to create an activity window or display that can show users what is going on and keep them informed of expensive operations that are going on inside LLDB.
Differential Revision: https://reviews.llvm.org/D97739
This patch adds a new command options to the CommandObjectProcessLaunch
for scripted processes.
Among the options, the user need to specify the class name managing the
scripted process. The user can also use a key-value dictionary holding
arbitrary data that will be passed to the managing class.
This patch also adds getters and setters to `SBLaunchInfo` for the
class name managing the scripted process and the dictionary.
rdar://65508855
Differential Review: https://reviews.llvm.org/D95710
Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
This patch exposes the getter and setter methods for the command
interpreter `print_errors` run option.
rdar://74816984
Differential Revision: https://reviews.llvm.org/D98001
Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
This patch adds a new command options to the CommandObjectProcessLaunch
for scripted processes.
Among the options, the user need to specify the class name managing the
scripted process. The user can also use a key-value dictionary holding
arbitrary data that will be passed to the managing class.
This patch also adds getters and setters to `SBLaunchInfo` for the
class name managing the scripted process and the dictionary.
rdar://65508855
Differential Review: https://reviews.llvm.org/D95710
Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
Our code for locating the shared library directory works via dladdr (or
the windows equivalent) to locate the path of an address known to reside
in liblldb. This works great for C++ programs, but there's a catch.
When (lib)lldb is used from python (like in our test suite), this dladdr
call will return a path to the _lldb.so (or such) file in the python
directory. To compensate for this, we have code which attempts to
resolve this symlink, to ensure we get the canonical location. However,
here's the second catch.
On windows, this file is not a symlink (but a copy), so this logic
fails. Since most of our other paths are derived from the liblldb
location, all of these paths will be wrong, when running the test suite.
One effect of this was the failure to find lldb-server in D96202.
To fix this issue, I add some windows-specific code to locate the
liblldb directory. Since it cannot rely on symlinks, it works by
manually walking the directory tree -- essentially doing the opposite of
what we do when computing the python directory.
To avoid python leaking back into the host code, I implement this with
the help of a callback which can be passed to HostInfo::Initialize in
order to assist with the directory location. The callback lives inside
the python plugin.
I also strenghten the existing path test to ensure the returned path is
the right one.
Differential Revision: https://reviews.llvm.org/D96779
It seems that recording fundamental return type is bogus.
This can trigger asserts when running a test with reproducers so this
patch updates the `SBTarget::IsLoaded` test to stop recording them.
Differential Revision: https://reviews.llvm.org/D95686
Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
This reverts commit 754ab803b8.
As pointed out in https://reviews.llvm.org/D95761, this patch could lead to
having the wrong execution context in some situations (thanks Jim!).
D92164 is addressing the same issue and will replace this patch, so I'll
revert this one.
This patch adds an `SBTarget::IsLoaded(const SBModule&) const` endpoint
to lldb's Scripting Bridge API. As the name suggests, it will allow the
user to know if the module is loaded in a specific target.
rdar://37957625
Differential Review: https://reviews.llvm.org/D95686
Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
Second try, handling both a bogus arch string and the "null file & arch" used
to create an empty but valid target.
Also check in that case before logging (previously the logging would have
crashed.)
Also revert "Follow on to: f05dc40c31d1883b46b8bb60547087db2f4c03e3"
After these changes, multiple lldb tests are failing. Calls to
CreateTargetWithFileAndArch(None, None) appear to fail after these
changes.
This reverts commit f05dc40c31 and
1fba21778f.
When you pass in a bogus ArchSpec, TargetList.CreateTarget
makes a target with the arch of the executable. That wasn't the
case with a bogus triple, so this change caused one of the bogus
input data tests to fail. So check that the ArchSpec is valid
before passing it to CreateTarget.
This patch introduces a LLDB_SCOPED_TIMER macro to hide the needlessly
repetitive creation of scoped timers in LLDB. It's similar to the
LLDB_LOG(F) macro.
Differential revision: https://reviews.llvm.org/D93663
This reverts commit a01b26fb51, because it
breaks the "finish" command in some way -- the command does not
terminate after it steps out, but continues running the target. The
exact blast radius is not clear, but it at least affects the usage of
the "finish" command in TestGuiBasicDebug.py. The error is *not*
gui-related, as the same issue can be reproduced by running the same
steps outside of the gui.
There is some kind of a race going on, as the test fails only 20% of the
time on the buildbot.
This patch exposes the Target::CreateBreakpoint overload with the
boolean argument to move to the neareast code to the SBAPI.
This is useful when creating column breakpoints to restrict lldb's
resolution to the pointed source location, preventing it to go to the next
line.
rdar://72196842
Differential Revision: https://reviews.llvm.org/D93266
Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
This patch exposes the Target::CreateBreakpoint overload with the
boolean argument to move to the neareast code to the SBAPI.
This is useful when creating column breakpoints to restrict lldb's
resolution to the pointed source location, preventing it to go to the next
line.
rdar://72196842
Differential Revision: https://reviews.llvm.org/D93266
Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
Currently, the interpreter's context is not updated until a command is executed.
This has resulted in the behavior of SB-interface functions and some commands
depends on previous user actions. The interpreter's context can stay uninitialized,
point to a currently selected target, or point to one of previously selected targets.
This patch removes any usages of CommandInterpreter::UpdateExecutionContext.
CommandInterpreter::HandleCommand* functions still may override context temporarily,
but now they always restore it before exiting. CommandInterpreter saves overriden
contexts to the stack, that makes nesting commands possible.
Added test reproduces one of the issues. Without this fix, the last assertion fails
because interpreter's execution context is empty until running "target list", so,
the value of the global property was updated instead of process's local instance.
Differential Revision: https://reviews.llvm.org/D92164
Pavel Labath